[gtk+] HC: include a missing sass function

[Jakub Steiner <jimmac src gnome org>]

commit f9ef67d2fad520ac058fdd192123de2bf7e87803
Author: Jakub Steiner <jimmac gmail com>
Date:   Tue Apr 28 00:33:17 2015 +0200

    HC: include a missing sass function
    
    - used in the color widget

 gtk/theme/HighContrast/_drawing.scss |    4 ++++
 gtk/theme/HighContrast/gtk.css       |    6 +++---
 2 files changed, 7 insertions(+), 3 deletions(-)
---
diff --git a/gtk/theme/HighContrast/_drawing.scss b/gtk/theme/HighContrast/_drawing.scss
index 330cb2e..4cb8b29 100644
--- a/gtk/theme/HighContrast/_drawing.scss
+++ b/gtk/theme/HighContrast/_drawing.scss
@@ -1,6 +1,10 @@
 // Drawing mixins
 
 // generic drawing of more complex things
+ function _widget_edge($c:$borders_edge) {
+// outer highlight "used" on most widgets
+  @return 0 1px $c;
+}
 
 @mixin _shadows($shadow1, $shadow2:none, $shadow3:none, $shadow4:none) {
 //
diff --git a/gtk/theme/HighContrast/gtk.css b/gtk/theme/HighContrast/gtk.css
index 7fec7d4..c244425 100644
--- a/gtk/theme/HighContrast/gtk.css
+++ b/gtk/theme/HighContrast/gtk.css
@@ -2542,13 +2542,13 @@ GtkInfoBar {
  * Color Chooser *
  *****************/
 GtkColorSwatch {
-  box-shadow: inset 0 1px rgba(0, 0, 0, 0.1), _widget_edge(); }
+  box-shadow: inset 0 1px rgba(0, 0, 0, 0.1), 0 1px #fff; }
   :selected GtkColorSwatch {
     box-shadow: none; }
     :selected GtkColorSwatch.overlay, :selected GtkColorSwatch.overlay:hover {
       border-color: #fff; }
   GtkColorSwatch:selected {
-    box-shadow: inset 0 1px rgba(0, 0, 0, 0.1), _widget_edge(); }
+    box-shadow: inset 0 1px rgba(0, 0, 0, 0.1), 0 1px #fff; }
   GtkColorSwatch.top {
     border-top-left-radius: 5px;
     border-top-right-radius: 5px; }
@@ -2573,7 +2573,7 @@ GtkColorSwatch {
     border-radius: 3px; }
     GtkColorEditor GtkColorSwatch:hover {
       background-image: none;
-      box-shadow: inset 0 1px rgba(0, 0, 0, 0.1), _widget_edge(); }
+      box-shadow: inset 0 1px rgba(0, 0, 0, 0.1), 0 1px #fff; }
     GtkColorEditor GtkColorSwatch:backdrop {
       box-shadow: none; }
   GtkColorSwatch.color-dark {